Compare Files Token by Token

You know how it is, you want to fix a bug in some code, but you have to
run it through indent(1) first, just to keep your sanity. When it
comes time to send a patch to the maintainer, you can't use diff(1) because
indent changed every line.

The contrast tool can show you a graphical diff, like
tkdiff(1) or
mgdiff(1), but it works token by token, rather than line by line.
This means that indent's changes to the white space are ignored.

That doesn't help you, even though you can see the just differences you
made, because your bug fix still isn't in the maintainers format. There
is a second tool which can effectively run indent backwards:
The contrast-reformat(1) tool is used to apply one file's format
to a second file. So, once you have the bug fixed, you can re-apply the
original file's insane formating (the white space between the tokens) to
to your bug fixed version. Now you can use regular diff(1) to
build the patch.